Method of continuous printing by lithography



C. P. summa. METHOD OF CONTINUOUS PRINTING BY LITHOGRAPHY.-

, APPLICATION FILED MAR.. I9', ISIO.

1,398,808. Patented Nov. 29, 1921.

UNITED si'Ai'asA PATENT onirica.

CHARLES P. STIRLING, OF SOMERVILLE, NEW JERSEY, ASSIGNOR T0 GOTT-A-LAP C0.,

' 0F SOMERYILLE, NEW JERSEY, A. CORPORATION 0F NEW JERSEY. i

METHOD OF CONTINUOUS PRINTING BY LITHOGRAPHY.

To all 'whom t may concern.'

Be it known that I, CHARLES P. STIRLING, a citizen of Austria, and a resident of Somerville, county of Somerset, State of New Jersey, (having declared my intentions of becoming a citizen of the United States have invented certain Improvements in Methods of Continuous Printing by Litho raphy, of which the following is aq spe'ci cation.

The objectof my invention is to print by lithography in continuous lengths. Hereto.

fore, it has been the universal practice in printing by lithography to print in s heets only, consequently, thel use of the printed sheet was limited and, furthermore, a considerable waste resulted in cutting, due to the fact that the sections had to be cut from comparatively small sheets. The in vention is 'particularly adapted for commercial purposes, such as the manufacture of covers for paper boxes, book bindings, etc'. At the present time, thesecovers are printed from engraved copper cylinders by the old and well known method of intaglio printing. This produces effects far inferior to` a litho graphic process. The present practice of lithography makes the cost prohibitive in many instances, owing to waste.

By my invention, which I will now proceed to describe, I ain enabled to print lithographically in continuous sheets of/any len th desired so that the lithographic'sheet wilIhave the same advantages in commercial manufacture as the sheet printedv by the engraved copper cylinder.

In the accompanying drawings, I have illustrated one method of carrying out my prlocess, the parts being shown diagrammatical Figure 1 is a sectional lview through a machine for graining the surface of a cylinder suitable to receive the design;

Fig. 2 is a view illustrating one form of apparatus for transferring the design onto the cylinder; and

Fig. 3 is a diagrammatic view of a lithographic printing. machine for making an impression on a continuous sheet of paper by the use of cylinders.

Specification 6i Letters Patent. i

Application led Hatch' 19, 1919. Serial No.

Patented Nov. 29, 1921. 283,468.

y cated in the trough-shaped base. The hopper is reciprocated by a crank 8 having a link 9 connected to one `end of the trough. '1 he crank is mounted on the end of a vertical shaft 10 driven from a horizontal shaft 11.y On the spindle of the cylinder 1 is a gear wheel 12, which meshes with the gear wheel 13 on a. driving? shaft 14 and on this shaft is a sprocket wheel 15 around which passes a chain'l to a sprocket wheel 17 on the shaft 11 so that, as the cylinder rotates, the trough is reciprocated. A number of smallballs 7 of'steehzor other suitable material, is placed in the hopper, as shown, and I also place in t-he hopper finely divided Hint with a given quantity of water so that,

as the cylinder is rotated, a certain amount of Hint passes between the balls and the cylinder, and the balls are agitated by the reciprocating hopper. This action causes the balls to force the flint against the cylinder and thus ain the surface in a manner suitable for lit ographic printing.

After the cylinder has been grained, it is removed from the machine illustrated in Fig. 1 and mounted in the machine illustrated in Fig. 2, which is a transfer machine; and consists of a bed 18 on which is mounted. a carriage 19 having bearings for a shaft 20 carrying a transfer drum 21 covered with rubber, or other suitable material. It also has bearings for the spindles of the cylinder 1 on which the design is to be transferred. Secured-to the bed 18 is a zinc plate 22 on which is the original design. When the roller 21 is rolled over this plate; 22, which has been previously inked up, the design is transferred onto the roller and finally transferred from the roller onto the cylinder 1. In the present instance, there is a rack-23 at each side of the bed 18 and a shaft 24 has pinions25 enga-ging the rack. On. the shaft is a gear wheel 26, which meshes with a pinion 27 on a shaft 2 8 having a handle 29 c by which it is turned.` -On the transfer roller 21 is a gear wheel 30 which meshesl -with one of the racks 23 and on the spindle of the cylinder 1 is a ear Wheel 31 which meshes with the gear w eel 30 so that when the carriage is traversed over the plate 22 all of the parts move in register. Care must be taken to have the'zinc late in exact proportion to the grained cy inder in order to produce the desired effect. Any visible defects on the grained cylinder 'are then retouched and the surface treated in the usual lithographie manner to bring it to the proper condition for printing. The ained rinting cylinder, with the design t ereon 1s taken from `the transfer apparatus and located in the printing machine, such' as illustrated in Fig. 3. Where two cylinders are used, the cylinder 1 may be duplicated, the number of cylinders depending upon the number of colors in the design.

In Fig. 3, I have illustrated in diagram one form of lithographie press which may be used in carrying out my invention. The two cylinders 1, 1 are mounted in position above an impression cylinder 32. The grained cylinders are geared to the cylinder 32 in the ordinary manner. Above each grained cylinder is an ink fountain 33 and a Water fountain 84C. V35 is an endless blanket and 36 is an endless delivery belt.

The roll of paper a is mounted on a rack 37 and the paper passes around tension rollers 38 and between the impression cyl-` inder and one of thegrained cylinders and over the impression cylinder and under the other grained cylinder, then around a 4guide roll 39 and over the endless belt 36 to the' From the above description it will be seen that by making the grained cylinder in the 'manner shown and by transferring the design onto the grained cylinder, the cylinder, or a number of these cylinders, can be mounted on a continuous printing machine so as to produce a continuous sheet having lithographie impressions thereon. This sheet is available for use for many purposes, such as a cover for aper boxes, book bindings, &c. A contlnuous lithographic sheet can be produced in colors by my improved process more cheaply than by the. present method of intagllo printing. Moreover, by printing in contlnuous sheets, considerable Waste is eliminated.

I claim:

The process herein described of preparb ing cylinders for making continuous impressions and printing therefrom, said process consisting in preparing a cylinder of zinc or similar material, graining the entire surface of the cylinder, then preparing a design on a flat zinc plate, the design being equal to the circumference of the grained cylinder, and iinally transferring the design from the flat zinc plate onto a transfer roller and from the roller onto the grained cylinder, preparing the cylinder for printing, and making a continuous impression on paper from the inked grained cylinder.

In Witness whereof I affix my signature.

CHARLES P. STIRLING 

